I don't use a hot wire cutter, too many fumes. I cut it with a box knife, blade extended or a 12" freezer knife. I've also tried a jigsaw at slow speed, very good for a smooth sided cut, but does make more dust. I no longer glue layers on top of each other, I've found it hard to disguise the joins. I now laminate vertically, to see any lines you need to be looking down on the layout, difficult when the lowest bit is 5' high!
I plan to use smaller bits, like the test pieces and fix them to the slopes as rock out crops.

Nearest Spaceboard is Wicks at Bicester 166 miles away! I see why it is not stocked much as it is not for use in new buildings or extensions.
Their Eco board should be better but none in stock at all!

I bought two sheets of the Celotex today. It is similarly fine grained to the pink stuff, but less dense. Probably not so good for laying track on but better for carving scenery, the use I want to put it to. I'll see if I have time to try a bit this weekend.

I use black and brown washes. I used to paint with solid grey first, but found in photos that there is a lot of white in granite, so now the washes go straight onto the white ceiling paint. I noticed many rocks have brown in them as well so the black wash is followed by a lighter brown wash

The black wash is 16ml of blackboard paint in a 30g coffee jar, the brown is 10ml of burnt umber tempera in another coffee jar.
Variation in colour comes from when the brush was last in the jar, plus bits get touched up if missed and that affects the colour as well. I tend to put a heavy brush full on and then use it until it runs out before doing another bit.

Another use for foam rocks I've found is in the river.
Rivers in the area I model often have large rocks washed down in the spring along their banks.
I needed something to cover the smooth side of my river where it was cut through the ply top. I have a load of stones that were left over from sieving out ballast from sharp sand, but they were a bit small and too rounded, but should be ok for the river bed.
I had some foam chips left from my new rock formations that I though would look ok, so I stuck some in place, they looked good so I ended up doing the whole of the river!

Once dry I'll wire brush them and then ceiling paint, before the washes the same as for the rock formations.

A few weeks on and some more scenery done. I've now add talus to the bottom of the cliff, and some further up. This is the large residue from sieving ballast from sharp sand, it matches the rock stain quite well.

There is a slight gap around the base of the rocks due to the fact that they have to lift out to access the board join inside the tunnel.

The first bridge girders are made up, I had to cut four panels out, which meant three cuts to keep the centre in the right place

Yes 5371 now has its' full number. It is weathered to represent the last year of operation, pushing up the mountains to Soldier Summit.

The layout is due another change, which will wipe out the last bit I worked on. I plan to remove the airing cupboard (after fitting new water heaters) so the layout can go into that area. As well as improving the scenery area,I can fit more storage loops under it. It will also make it easier to go through the wall and out onto the landing, a possible future branchline.

Well after a two year hiatus I have finally removed the airing cupboard and have plans for the new corner.

The old layout hanging off the cupboard.

Now removed, an extra 10 square feet of space. Note the two main tools used, a crowbar and a multitool.
I still need to redo some plaster and timber work to finish the walls.

The new plan, the cupboard was in the bottom left. The storage loops will be lengthened from the right corner to the left corner. The track plan will stay nearly the same, the extra length on the inner track climbing up will allow a greater height so I can move the grade further back over the end of the main yard (not shown on this plan). Timber Creek spur moves to the inside leaving a space for more mountains in the corner.

As well as the area shown on the plan,which gives more space for scenery I'm hoping the extra height reached by the inner track will sort out the unsatisfactory point where it crosses over the end of North Fork Springs yard. If I can push it out further I can get it behind a back scene, instead of the implausible bridge it crosses at the moment.

This shows it before scenery was installed, the right end of the climb should be over an inch higher, 2' will be added in the middle of this shot, if that gives enough clearance over the storage tracks (with the train on it) I can move the track out of the way of the yard end.